Oliver joseph lodge



Patented Aug. 6, i898. U. J LODGE. ELECTRIG TELEGRAPHY.

4 (Application filed Feb. 1, 1898.)'

(N e Pil u qi e I l 2 Sheets-Sheet I.

Patents@ Aug. 86, M898.

uw. @mgm (No Model.)

. whereby parts, of the'I emitting arrangement UNITED `STATI-3s Afl-ENT '-FICEQ i oLivER JOSE-P11 LODGE, ,or LivEarooL, ENGLAND.

ELECTRIC TELEcRAPi-iv.

sPEcIVErcATIoN forming pm of- Letters-resent No. 609,154, dated' August "1e, ieee. Application filed February 1, 1898. Serial No. 668,.'152f (No model.)

To all -whont it may concern.-

Be it known that I, OLIVER JOSEPH LODGE,

i a subject of the Queen of Great Britain, re-

siding at Liverpool, in the county of Lancas ter, England, have invented certain new and useful Improvements in Electric Telegraphy,

of which the following is a specification.

,The object of my invention is to enable an operator, by means ofwhat is now known as llertzian-wave telegraphyf to transmit mes- 'sages acrossspace to any one or more of a number of diierent individuals in various localities, each of whom is provided with a and claimed. 4

The method of intercommunicaton consists, according to my invention, in utilizing certain processes and apparatus for the purpose of producing and detecting a sufficientlyprolonged series of rapid electric' oscillations and in so arranging them that the excitation of a particular frequency of oscillation at the sending-station may cause a telegraphic inv strument to respond at a -distant station by reason of being associated, througha relay or otherwise, witha subsidiary circuit capa ble of electric oscillations of that same par-- ticular frequency or of some multiple or submulti ple ofthat frequency. Another distant station will similarly be made to receive niessages by exciting at the sending-stations ail diagrammatic representationsJiigure 1 shows ternations of a diierent frequency, and so o n, and thus'individual messages can be transmitted toi'ndivid ual stations without disturbing the receiving appliances at other stations which are tuned or timed or syntonized to a different frequency. Each station will usually be provided with bothsending and re- I cciving apparatus. s

In the accompanying drawings, which are the simplest arrangement of emitter andreceiver heretofore in use. and show alternative arrangements. to be adopted at signaling-stations or appendages thereto in accordance with my invention. Fig. ,3, in addition` to showing van emitter, serves to show a receiving-circuit and means Figs. 2, 4,6,.7, 8; 9, i.

. is utilized for receiving purposes.' Fig. 5 depicts the` more prominent features of a longdistance arrangement, Vbioth sending and ireceiving.

syntonic `receiving-circuit with appendages, and Fig: 1 1 is a detail view hereinafter more particularly referred to. i

Like letters and figures of reference indicate vsimilar parts throughout the drawings.

A complete installation of IIertzian-wave telegraphy consists, iii-its simplest form,of the arrangement depicted .in Fig. 1, wherein A .represents theemitting apparat-us, and B the receiving apparatus.l -I I In the emitter illustrated in'iig. 1 eleckorff coil a, is supplied to a pair of conductors which discharge into each other from knobs Vli and c and thus excite oscillations,A

which emit one or two waves before they are damped' out.

of a collector d, a coherer e, a battery f or atelegraphic receiving instrument g, all. in electrical connectiomas shown.

,In carrying out my invention, and referring nowV to the'subsequen't figures'of the draw ings, I use a definite radiator consisting of a conductor or pair of conductors h h' of large capacity, arranged either as aLeyclen jar or preferably one of them being the earth when desired. I join to '-h 'and h', respectively, which I denominate capacity areas, a pair of polished knobs h2 h3, protected by glass from ultravioletligiit, which form the adjustable sparkgap. Between either capacity area and its vknob I place a syntonizing self-ind-uctance '71.4, preferably insulated with any solid or iluid insulator, as in Fig. 2, or in air, of shape suitable to attain greatest inductance with a Figs. 12 and 13 illustrate alterna tive forms of connection of apparatus in a The receivlng-circuit consists, essentially,

spread out' separately in space,V

coil-that is, a coil of wire or metallic ribbon tricity from a suitable source,sucl1 as a Ruhml other suitable source of electrical energy, and

to prolong'the electric oscillations Aoccurring in the radiator, seas to constitute -v it a radiator of definite frequency or pitch and obtain a succession of tone-waves emitted, and thereby to render syntonyjin a receiverpossible, because exactitude of, re-

spense depends on the fact that the total number of oscillations in a suitably-arranged circuit is very great, so that a very feeble impulse is gradually strengthenedby cumulative action until it causes a perceptible eect lon the Well-known principle of sympathetic machine a to the two knobs h2 h3, which is the customary plan and gives a discharge which follows upon fairly steady electric strain. Y

The second way consists, as shown in Fig. 3, in having a supplementary pair of sparkgaps h6 h7, (which I call the supply-gaps,) one knob of each (called the receivingknob) being attached to the middle or other convenient point of each capacity -area h h', and the other knob of` each pair (called the supply-knobs being connected by wires hB to the Ruhmkorft coil and brought moderately near the first, so that when the coil is in actionv the capacity areas shall receive their positive and negative charge by aerial disruption-thatis, in a sudden manner-rather than by the slower process of metallic conduction, and shall then be left to discharge into each other through the connecting-coil h4 and across the shortspark-gap between the knobs h2 h3, The 'best width of this gap depends upon circumstances, and it 4may be closed altogether without stopping the action.

The gap between the knobs h2 h3 may be op-l tionally closed by a shunt hg.

vIn the third plan, as indicated in Fig. 4, I interpose in each of the wires h? leading from the Ruhmkorff coil a to the supply-knobs a Leyden jarjor other suitable condenser j able to stand a high potential, so that the knobs are supplied from the outer--that is, the uninsulated-coat of each jar, while between the inner 'coats or coil-terminals I arrange a third spark-gap, (called the starting-gap,.) also consisting of suitable knobs hw hn.' The outer coats of the jars must not be insulated from each other, and I usually join them by an induction-coil of fairly thin wire k, so as to permit thorough charging. When the-discharge occurs, this wire acts as an alternative path or by-pass, but does'. not prevent the sparks at the supply-gap.

,- By both of the means described with reference to Figs.' 3 and 4 I charge the two capacity areas h h' (which, together with the inductance-coil between them, constitute the radiator) by y'aerial disruption or impulsive rush. The advantage of this is that charges so communicated are left to oscillate free from any disturbance due to maintained connection with the source of electricity, and there fore oscillate longer and more simply than,

knobs h2 h3.

when supplied by wires in the usual way. Moreover, the capacity areasof a radiator are more conveniently employed as the capacity method of charging the capacity areas h h with an impulsive rush. The action is as follows: The Ruhmkori machine a charges the jars y, whose outer coats are connected, and

discharges them at the starting-gap h1". This spark precipitates a discharge at the supplygaps h6 h7 and suddenly supplies the capacity areas h h with electric charges, which then surge through the connecting-coil h4 (divided into two parts in this ligure) and sparkinto each other at the discharge-gap between the This last discharge is the chief agent in starting the oscillations which are the cause of the emitted waves; but it is permissible inthe arrangements of Figs. 3 and 4 to close this last gap when desired andso leave the oscillations to be started by the sparks at the supply-gaps only, whose knobs mustinthat, caseibe polished and protected from ultra-violet light, so asl to supply the electric charge, in as sudden a manner as possible. t

As charged surfaces or .capacity areas spheres or square plates or any other metal surfaces may be employed; but I prefer, for the purpose of combi-nin g lowresistance with great electrostatic capacity, cones or triangles or other such diverging surfaces with the vertices adjoining and. their larger areas spreading out into space; or a single insulated surface may be used in conjunction with the earth, the earth or conductors embedded in the earth constituting the other oppotance signaling Vis 'shown on. the left-hand side of Fg.' 5. Fig. 6 shows a single insulated capacity area h with the earth acting as the other surface-and leading up to the spark-knobs h2 h.3 by a triangular sheet ol.'

cone h', so as to afford good conductance even to rapidly-alternating current-s. The wire h8 in this case leads to one terminal of the Ruhmkori coil, theother terminal of which is' taken to earth.. The capacity area h is insulated, as indicated at h2.

Incases. where it is required that the appav ratus shall offer less' ,resistancey to wind t e arrangement may be such as that illustrated which insulator divides-the upper from the'- lower part of the rod carryingthe dischargeknob h3. The spiral h4 bridges over the gap thus caused, uniting the rod above and' be` low the insulator and so affording an earth connection.

' Fig.` Sshows an insulated metal surface in the form of a roof of a shed or building which may be used as a capacity area, with suitable connection and apparatus (not shown) insidethe little house l. The self-inductance coil represented at h4 in all applicable figures is a coil of highlyconduct-ing wire or ribbon, well insulated byl air or by some other medium, as already described, or else covered to a suiiicient thickness with insulating material of such shape as to liave'maxirnum self-inductance for a given resistance, and it may be either a'lat coil inclosing a considerable plane area or it may bea cylindrical coil wound upon 'a finelysubdivlded iron core, as shown at m in Fig.

9, the core beingleither ring-shaped or Uf shaped or straight. v

The discharge-knobs h2 h? may be arranged at one end of such coil, as shown in Figs. 2,

3, 7,. and 9, or the coil may bein two halves with the knobs inserted in the middle, at pleasure. v(See Figs. 4 and 5). Several such coils h4 h'1X him, with their knobs h2, 713x, and

hm", may, as shown in Fig. 10, be arranged for use with a single pair of capacity areas, and any one of them may be brought into action by a suitable switch, so that the desired frequency of vibration or syntony with a particular distant station is attained by replacing onecoil by another, for the frequency can be' adjusted either by varying the casition of coils or other portion of the dis pacity of the condenseror jar or other conf ductor employed or the charged 'body on the one hand or by varying the' number and pocharge-circuit on the other. That discharger is in action yWhose spark-gap is allowed to ope1ate,and a switch A 5 C can determine which of a set of different coils shall bentilized for a given distantJ station. Fig. 11 illusltrates the form of switch indicated in Fig. l0,

. ln Fig. 1l the numeral-l designates a metallic union-piece. 2 is its handle, of insulatingy material', and 3 lis a suitable insulating-base. The union-piece l dips into mercury-cups 4c and 5, with Whichthe leads (il and 7 are connected. 4

largepoil of a considerable-n umher of turns,as-

shown in Fig. 9, and to have keys or plugs or switches' s and s2, whereby some of the spires or turns of the coil can be shunted out of acand adapted'togrip. the levers when they are depressed, so as to make good contact. Thus each 1ever.when pressed down shuts out allv the spires of the coil between the two endsof such leven/This arrangement may be n Y either in lieu of or in combination with interchangeableindnctance-coils, such as shown in Fig. 10, and in the lattercase theyare useful for correcting slight errors in tuning for any one station. The one I call an adjustableicoil and the other I callreplaceable or interchangeable coils, and both, since they tend to a like end and behave similarly,-

may be included by the terni variably-actlA receiver or resonator consists of a simii lar pairof capacityareas connected by a similarly shapedl conductor or self inductance coil, the Whole constituting au absorber arranged so as tolhave precisely 'the same natural frequency of electrical vibration as Ythe radiator innse at the corresponding emittingstation, so that it can accumulate the received impulses-that is to say, can act cumulatively; but it must not have a spark-gap, such as h2 h3, or if vit have a spark-gap the same must be carefully closed or shunted or lbridged` across by a goed short conductor-for example, like Fig. ll-before the arrangement can) be properly used as a cumulative receiver. Identically the same capacity areas and selfinductance coil can be used at will either as emitter or as receiver-that is, eitheras radi.`

nog

Vator or as resonator (see Fig. 5)-if it be um convenient to do so, on condition that the" discharge spark-gap h2 ha olf the radiator is perfectly closed whenever acting as receiver.` 4

Thus referring to Fig. `3 it `will be seen that' that diagram illustrates a combined emitting and receiving apparatus. lVhen in use, .asa radiator, the gap between the discharge-knobs4 h2 h3 is left open. nator, the said gap is vclosed by the shunt h, (there supposed to be like Fig. 11,) and the. coherer e, batteryf, and'telegraphic reccivf ing instrument g are connected throughathin wire w from each end of the coil 7a4-that is,- from each of the capaci areas.

rig

When l utilized as a resorag lf the RuhmlrorlA machine a has been actnally connected tothe capacity areas h h', as in Fig. 2, then it must be detached and substituted by the coherer-circuit when a receiver is wanted; but lif lthe charge was supplied through supply-gaps h6 h", as inw Figs. 3'and 4, (and this is the best plan,) then the Ruhmelectric impulse and rises to its old resistance on being subjected to a mechanical impulse,

such as a tremor or a tap. A coherer-circuit is any known arrangement for observing or recording effects due to fluctuations in the electrical resistance of a coherer. f

As cohcrer I use either a light single-.point contact or Branlys arrangement of a pair ofv conductors embedded in metallic grains or l pwwder or filings; but I prefer selectcdironfilings of uniform size sealed up in a good vacuum and with the communicating surfaces or electrodes reduced to points or thin platinum wires fused into the glass and 'with their ends close together; or I may use any other suitable apparatus with an appropriate device for tapping back. In some cases I find that a eoherer restores itself sufficiently without specially-arranged tremor and that in these cases a telephone is the quickest responder that can be used.

As coherer-circuit I usually arrange the coherer in simple series with a battery (voltaic or thermal) and a galvanometer, telephone, i

or lother indicator, or a recorder of fluctuations of current, and I then connect the ter.- minals of this series of instruments to the capacity areas of the receiver close to its selfinductancecoil, so that this same coil of wire vcourpletes and forms an essential part of the co'- herer-circuit. The coherer is thus affected'by every electrical disturbancev occurring in the connecting-coil or in its capacity areas and by aid of the battery at once enables the telegraphic or telephonie instrument to appreciate and indicate the signals. This plan is shown in Figs. 3 and 1,2. It is an improvement, on any mode of connection that hao previouslybeen possiblel without the connecting-coil. l

In some cases I may, as shown 1n Fig. 13,

surround the syntonizing-coii of the resonator with another or secondary coil u (constituting a species of transformer) and make'this latter coil part of the coherer-circuit, so that' it shall be secondarily affected by the alternating currents excited in' the conductor of the resonator, and thus the coherer be stimulated by the current in this secondary coil rather than primarily by the currents in. the syntonizing-coil itself, the idea being thus to leave the resonator freer to vibrate electrically without disturbance from attached wires.

In all cases it is permissible andsometimes desirable to shunt the coils of the telegraphic instrument by means of a resistance or a capacity, as shownat w in Fig. 12, in order to connect the coherer more effectively and.'

closely to the capacity areas or receiving arrangement whereby it is to be stimulated.

Vhat I claim, and desire to secure by Letters Patentof the United States, isl 1. In a system of Hertzian-wave telegraphy, the combination,with a pair of capacity areas, of aself-inductance coil inserted between them electrically for the purpose of prolonging any electrical oscillations excited in the system and constituting such a system a raf diator of definite frequency or pitch.

2. In a system of IIertzian-wavc telegraphy,

the combination,with a pair of eapacityareas, of a vself-inductance coil inserted between them electrically for the purpose of prolonging any electrical oscillations excited in the system, thus constituting thel system a resonator or absorber of definite frequency or pitch, and a distant radiator of 'corresponding period capable of acting cumulatively.

3. In a system of IIertzian-wave telegraphy, the eombinatiomwith a pair of capacity areasof electrical means having a spark-gap nserted between them and serving to syntonize them and means for bridging or shunting the spark-gap,whereby the apparatus is adaptable for use at will either asa radiator or resonator.

4. In a system of IIertzian-wave telegrapliy, the combination, with a pair of capacityareas, of a number of self-inductance coils having different amounts of self-induction each of which is capable of being switchedin or out of circuit, serving to lsyntonizc any such radiator to a corresponding resonator or vice versa,whereby signaling may be effected between any two or more correspondingly-attuned stations without disturbing other differently-attuned stations.

5. In a system of I-Iertzian-wave telegraphy, the combination, with a pair of capacity areas, of a variably-acting self-inductance coil-7 serv ing to syntonize such a radiator or resonator to any other such resonator or radiator, whereby signaling may be effected between any two o'r more correspondinglyattuned stations without disturbing other differently-attuned stations.

(i.v In combination, a pair of capacity `areas connected by a coil of wire serving .as the radiator in a system of IIertzan-wave telegraphy, means for syntonizing such radiator, and means for charging it by aerial disruptionor impulsive rush. 7. In a system oflIertzian-wave telegraphy, the combination of a pair of capacity areas such as h, h', means for syntonif/.ing such capacity areas, a receiving-circuit completed through one or both of such capacity areas, and means for gap between such capacity areas when they are to be used as a receiver, whereby such capacity areas are rendered adaptable for use at .will either as a radiator or resonator.

8. In combination, 1n al system of syntonic bridging over the discharge-` 4which secondary coil forms part of the cohcrer-circuit substantially as and fox` the pureo9,154 5A coil surrounding said self-inductance coil, across the coils thereof substantially as and 1c for the purpose set forth.

In testimony whereof I have hereunto sub- `pose set forth. h scribed my name.

9. The combination in t e receivinU-ciicuit'ofasystemof Hertzien-wave telegraphy, OLIVER JOSEPH LODGE.

necting the capacity areas, a coherer, a. bat- A. F. SPOONER,

of a variably-acting self-nductance coil, con- Vvitnesses: tery, a, receiving instrument, and aJ shunt l J. SUTTON. 

